Generally, disc-type coin sorters sort coins according to the diameter of each coin. Typically, in a given coin set such as the United States coin set, each coin denomination has a different diameter. Thus, sorting coins by diameter effectively sorts the coins according to denomination.
Disc-type coin sorters typically include a resilient pad (disposed on a rotating disc) that rotates beneath a stationary sorting head having a lower surface positioned parallel to the upper surface of the resilient pad and spaced slightly therefrom. The rotating, resilient pad presses coins upward against the sorting head as the pad rotates. The lower surface of sorting head includes a plurality shaped regions including exit channels for manipulating and controlling the movement of the coins. Each of the exit channels is dimensioned to accommodate coins of a different diameter for sorting the coins based on diameter size. As coins are discharged from the sorting head via the exit channels, the sorted coins follow respective coin paths to sorted coin receptacles where the sorted coins are stored.
It is desirable in the sorting of coins to discriminate between valid coins and invalid coins. Use of the term “valid coin” refers to coins of the type to be sorted. Use of the term “invalid coin” refers to items being circulated on the rotating disc that are not one of the coins to be sorted. For example, it is common that foreign or counterfeit coins (e.g., slugs) enter the coin sorting system. So that such items are not sorted and counted as valid coins, it is helpful to detect and discard these “invalid coins” from the coin processing system. In another application wherein it is desired to process (e.g., count and/or sort) only U.S. quarters, nickels and dimes, all other U.S. coins including dollar coins, half-dollar coins and pennies are considered “invalid.” Additionally, coins from all other coins sets including Canadian coins and Euro coins, for example, would be considered “invalid” when processing U.S. coins. Finally, any truly counterfeit coins (i.e., a slug) are always considered “invalid” in any application. In another application it may be desirable to separate Canadian coins from U.S. coins for example. Therefore, in that application all authentic U.S. and Canadian coins are considered invalid, and all non-authentic U.S. and Canadian coins and all coins from other coin sets (e.g., Euro coins) are considered invalid.
Typically, prior-art disc-type coin sorters include a discrimination sensor disposed within each exit channel for discriminating between valid and invalid coins as coins enter the exit channels. In such systems, therefore, coins entered the exit channel and are then discriminated. An invalid coin having a diameter that enables it to pass into an exit channel moves past the discrimination sensor. The discrimination sensor detects the invalid coin and a braking mechanism is triggered to stop the rotating disc before the invalid coin is moved out of the exit channel. A diverter, disposed within the coin path external, or internal, to the sorting head, moves such that a coin entering the coin path is diverted to an invalid coin receptacle. The sorting head is then jogged (electronically pulsed) causing the disc to incrementally rotate until the invalid coin is discharged from the exit channel to the coin path where it is diverted to a invalid coin receptacle. The diverter is moved back to its home position such that coins now entering the coin path are directed to the coin receptacles for valid coins. The coin sorter is then restarted and the disc begins to rotate at the normal sorting rate of speed.
One drawback associated with this type of prior art discrimination technique is the downtime consumed by the aforementioned stopping, jogging and restarting of the rotatable disc to remove the invalid coin. This process often takes approximately five seconds per invalid coin. Initially, this may appear to be a relatively insignificant amount of time; however, this time can add up to a significant amount of time in the processing of bulk coins.
Furthermore, because the rotatable disc rapidity breaks and stops so that an invalid coin is not ejected from a coin exit channel before the diverter is moved to route invalid coins to a reject receptacle, the overall speed (i.e., the number of rotations of the rotatable disc per minute) is limited. Additionally, this type prior art discrimination technique results in more “wear and tear” on the breaking system and motor.
Accordingly, a need exists for a coin processing machine that can discriminate invalid coins at a high-rate of speed.